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Liz Nayibe Martínez Saavedra Ricardo Gonalves Penido Lucas de Azevedo Santos Teodorico C. Ramalho Bruno E. Lobo Baeta Mrcio C. Pereira Adilson Candido da Silva 《RSC advances》2018,8(50):28775
The effects of solvent on the synthesis of molecularly imprinted polymers (MIPs) for the selective adsorption of quinoline were evaluated in this work. The MIPs were synthesized by the “bulk” method using the quinoline molecule (IQ) as a template in different solvents, such as toluene (MIPT) and chloroform (MIPC). The adsorbents were characterized by thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and N2 adsorption/desorption measurements. The influences of time, adsorbate concentration, and temperature on the adsorption of quinoline by MIPT and MIPC were evaluated. Maximum adsorption capacities (qe) of 35.23 and 24.10 mg g−1 were obtained for MIPT and MIPC, respectively. Thermodynamic studies indicate that occur physisorption and a spontaneous process (ΔadsG° < 0) entropically directed. Finally, the highest selectivity and reusability of MIPC for quinoline adsorption was ascribed to the better interaction between the chloroform and monomer, which favors the formation of porous adsorbents with higher numbers of adsorption sites.Molecularly imprinted polymers synthesized by a one-pot synthesis absorb quinoline efficiently and selectively. 相似文献
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Frota Filho JD Drews C Leães P Blacher C Tostes F Delatorre N Vieira M Lúcio E Pereira W Sales M Lobo R Stuermer R Tanaka N Portugal L Lucchese F 《Arquivos brasileiros de cardiologia》2001,76(3):245-254
Necrotizing fasciitis is a rare soft tissue infection and a life-threatening emergency, often fatal. Its incidence and management are described plentifully in the medical literature regarding the most common anatomical sites involved like the abdomen, lower and upper limbs, and perineum. However, available data and case reports of chest wall necrotizing fasciitis after thoracic procedures are scarce, mainly after major cardiac operations. We report and discuss a case of necrotizing fasciitis of the chest wall occurring in the immediate postoperative period of a cardiac procedure, and include a brief review of the concepts, pathophysiology, and treatment reported in the medical literature. We emphasize the need for early diagnosis and urgent and effective surgical debridement. Of importance is the fact that we have not found any references in the literature to cases similar or equal to the one we describe here, which occurred in the postoperative period of a cardiac procedure. 相似文献
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Evidence for the importance of peripheral tissue events in the development of hirsutism in polycystic ovary syndrome 总被引:2,自引:0,他引:2
R A Lobo U Goebelsmann R Horton 《The Journal of clinical endocrinology and metabolism》1983,57(2):393-397
Hirsutism can occur in the presence of normal or near normal levels of serum testosterone, unbound testosterone (uT), dehydroepiandrostene sulfate, androstenedione, and dihydrotestosterone. However, we have found that serum androstanediol glucuronide (3 alpha-diol G) is markedly increased in idiopathic hirsutism and it serves as an excellent marker of peripheral androgen metabolism and action. In the present work, we studied 12 hirsute (H) and 12 nonhirsute (NH) patients with polycystic ovary syndrome (PCO) and 13 age and weight matched controls in order to determine if differences in sex steroid levels or peripheral tissue androgen events were associated with hirsutism. Serum unbound estradiol levels and LH-FSH ratios were similar in both groups of women with PCO, and both were significantly higher than levels in controls (P less than 0.05). Whereas serum testosterone, uT, and androstenedione were elevated in both H-PCO and NH-PCO patients compared to controls, the levels in these two groups were similar. Serum dehydroepiandrostene sulfate was higher in PCO patients compared to controls, but H-PCO patients had slightly higher levels than NH-PCO patients. Serum delta 5-androstenediol was also slightly higher in H-PCO compared to NH-PCO patients. Dihydrotestosterone was normal and unconjugated; 3 alpha-diol was higher than normal in both groups of patients with PCO, although H-PCO patients had higher levels than NH-PCO patients. Compared to these relatively minor changes between the PCO patient groups, serum 3 alpha-diol G was markedly elevated in H-PCO patients (approximately 10-fold), yet normal in NH-PCO patients (P less than 0.01). The ratios of serum 3 alpha-diol G-uT were similar in NH-PCO patients and controls, but were elevated in H-PCO patients (P less than 0.01). These data indicate that: 1) women with PCO have increased circulating androgen levels regardless of the presence or absence of hirsutism; and 2) the presence of hirsutism is not only a function of circulating androgen levels, but may also be determined by events in peripheral tissues. 相似文献
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Hurlstone DP Shorthouse AJ Cross SS Brown S Sanders DS Lobo AJ 《Techniques in coloproctology》2004,8(3):173-178
Abstract
Background
Persistence of underlying disease in the residual rectal mucosa and anal transition zone (ATZ) following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis and familial adenomatous polyposis provides a site for potential malignancy. For this reason endoscopic surveillance is performed, although conventional assessment may be unreliable. We hypothesized that the novel technique of high-magnification chromoscopic pouchoscopy (HMCP) may permit accurate anatomical localization of this high risk zone in vivo and permit improved biopsy accuracy.
Patients and methods
We studied 132 patients with IPAA using HMCP. Three distinct zones were defined using magnification endoscopy: ATZ, appearing as a linear cellular marix; columnar cuff, identifiable by a type I crypt pattern; and ileal pouch body, appearing as villous projections. Quadrantic biopsies of these zones were taken in addition to biopsies of any other lesions noted.
Results
A total of 1586 biopsies were taken from zones 1–3 (median, 12; range, 5–16 per patient). Overall biopsy-targeting accuracies using magnification guidance as compared with histopathology were 82%, 73% and 91% for the ATZ, cuff and pouch body, respectively. No dysplasia was identified in the quadrantic surveillance biopsies. Histologically confirmed columnar metaplasia was visualized in vivo using magnification chromoscopy. Patients with IPAA >3 years duration were more likely to have pouch reservoir columnar metaplasia as compared to those <3 years (p<0.01). Pouch reservoir metaplasia was associated with a pre-morbid diagnosis of high-grade dysplasia or carcinoma within the premorbid colectomy specimen (p<0.001).
Conclusions
This is the first study to evaluate this novel application of high magnification chromoscopy. Magnification pouchoscopy is a valid predictor of ATZ and cuff anatomy, permitting accurate biopsy targeting. Further randomized studies validating this technique with an emphasis on dysplasia detection in larger cohorts are required. 相似文献
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Julieta Afonso Adhemar Longatto-Filho Olga Martinho Francisco Lobo Teresina Amaro Rui M. Reis Lúcio L. Santos 《Virchows Archiv : an international journal of pathology》2013,462(4):445-453
Urothelial bladder cancer (UBC) is a heterogeneous type of disease. It is urgent to screen biomarkers of tumour aggressiveness in order to clarify the clinical behaviour and to personalize therapy in UBC patients. Raf kinase inhibitory protein (RKIP) is a metastasis suppressor, and its downregulation is associated with metastatic events in an increasing number of solid tumours. We evaluated the clinical and prognostic significance of RKIP expression in patients with high risk of progression UBC. Using immunohistochemistry, we determined RKIP expression levels in a series of 81 patients with high-grade pT1/pTis or muscle-invasive UBC. Staining of CD31 and D2-40 was used to assess blood and lymphatic vessels, in order to distinguish between blood and lymphatic vessel invasion (LVI). We found that 90 % of pT1/pTis tumours, 94 % of non-muscle invasive papillary tumours and 76 % of the cases without LVI occurrence expressed RKIP in >10 % of cells. In this group, we observed a subgroup of tumours (42 %) in which the tumour centre was significantly more intensely stained than the invasion front. This heterogeneous pattern was observed in 63 % of the cases with LVI. Low RKIP expression was associated with poorer 5-year disease-free and overall survival rates, and remained as an independent prognostic factor for disease-free survival. Loss of RKIP expression may be an important prognostic factor for patients with high risk of progression bladder cancer. 相似文献
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